8.15 REREAD

The REREAD transformation allows the previous input line in a
data file
already processed by DATA LIST or another input command to be re-read
for further processing.

The FILE subcommand, which is optional, is used to specify the file to
have its line re-read. The file must be specified as the name of a file
handle (see File Handles). If FILE is not specified then the last
file specified on DATA LIST will be assumed (last file specified
lexically, not in terms of flow-of-control).

By default, the line re-read is re-read in its entirety. With the
COLUMN subcommand, a prefix of the line can be exempted from
re-reading. Specify an expression (see Expressions) evaluating to
the first column that should be included in the re-read line. Columns
are numbered from 1 at the left margin.

The ENCODING subcommand may only be used if the FILE
subcommand is also used. It specifies the character encoding of the
file. See INSERT, for information on supported encodings.

Issuing REREAD multiple times will not back up in the data
file. Instead, it will re-read the same line multiple times.